Typically, a Cardiologist, or Invasive Cardiologist performing an intravascular procedure first uses a needle to create a percutaneous puncture into the artery. A guide-wire is then placed, via the needle, through the puncture site into the artery. The needle is withdrawn and a conventional percutaneous introducer sheath is placed over the guide-wire. The introducer sheath extends into the channel of the artery and serves as a means for medical instruments to be inserted and removed as necessary to perform the operative procedure. Once the operative procedure has been concluded and the medical instrument and introducer sheath are removed, it becomes necessary to stop bleeding at the puncture site. Note particularly that the size of the opening of the puncture may vary greatly depending upon the procedure being performed. For example, the opening can range from as little as 1.67 mm to 2.67 mm (5 to 8 French) for a standard angiography procedure to as much as 6.0 mm to 6.67 mm (18 to 20 French) for cardiopulmonary support systems. The opening may be further enlarged by prolonged manipulation of various catheters, sheaths and instruments entering and exiting the treatment site.
Conventional medical practice with respect to the closure issue has been to simply apply external manual pressure to the puncture site for as long as it takes for hemostasis or clotting to occur. While effective ultimately, the conventional practice suffers from a number of drawbacks. The length of time that pressure is required in order to induce clotting may run as long as 45 minutes in the case of punctures into femoral arteries, or even longer if the patient has been pre-treated with anticoagulant medication. At best, such prolonged external pressure results in pain, substantial post-operative bruising and extended recuperative stays; at worst, excessive pressure for an extended period of time can result in development of a pseudo-aneurysm or severe hematoma. Moreover, from the perspective of economic efficiency, this practice is viewed as a wasteful use of the precious time of physicians and other highly skilled medical personnel.
There have been relatively recent attempts made in the prior art to find alternate solutions to the puncture site closure problem. For example, Kensey in U.S. Pat. No. 4,890,612, describes a device comprising plug means, a holding portion to hold the plug means in place, and a sealing portion formed of foam hemostatic material. Unfortunately, this device leaves a foreign body in the arterial lumen, which body may dislodge and embolize the artery. In addition, Kensey fails to provide a means for positively locating the puncture site in the blood vessel.
Sinofsky, in U.S. Pat. No. 4,929,426, employs a semi-rigid tube having an inflatable balloon, which after proper positioning, is inflated to apply pressure directly to the outside of the arterial wall. Laser energy is then directed to the site, via an optical fiber in the tube, to thermally weld the artery and seal the puncture. This device suffers from being relatively expensive and overly complicated. In addition, as with Kensey, there is no means to positively locate the puncture site in the arterial wall.
Fowler, in U.S. Pat. Nos. 5,108,421 and 5,275,616, uses a balloon catheter, or alternatively a cylindrical insertion assembly having a proximal plunger member associated therewith, to position an implantable vessel plug into the puncture site, which plug is over time absorbed into the surrounding tissue. This device suffers the shortcoming that the vessel plug can slide along the side of the balloon catheter causing improper plug positioning. And, once again, there is no means to positively locate the puncture site.
Gershony et. al., in U.S. Pat. No. 5,383,896, provide a percutaneous sealing device with a shaft through which a balloon is inflated and withdrawn until the balloon hemostatically engages the inner surface of the blood vessel. Inflation pressure is then maintained until clotting seals the puncture site. But since both the vessel and the balloon are compliant, the device can easily be drawn through the puncture site, thus defeating the purpose. Nor is any means for positively locating the puncture site provided.
Klein et. al., in U.S. Pat. No. 5,417,699, resort to a suturing approach wherein needles and suture material are introduced into the lumen of a body structure via a narrow shaft, and configured in such a manner that when passed back through the tissue a loop of suture is left behind which, when tied, completes closure of the puncture site. Here again, absent means to positively locate the puncture site (and with no way to assure the device is properly centered), Klein's needles may not suture the artery at the appropriate spot.